The maritime administrative department employs synthetic aperture radar (SAR) satellite remote sensing technology to obtain evidence of illegal discharge of ships. If the ship is discharged during navigation, it forms...The maritime administrative department employs synthetic aperture radar (SAR) satellite remote sensing technology to obtain evidence of illegal discharge of ships. If the ship is discharged during navigation, it forms a long dark wake on the SAR image due to the suppression of the Bragg wave by the oil fi lm. This study investigates key techniques for rapid detection of long ship wakes, thereby providing law enforcement agencies with candidate ships for possible discharge. This paper presents a rapid long ship wake detection method that uses satellite imaging parameters and the axial direction of the ship in images to determine the potential detection area of the wake. Then, the threshold of long ship wake detection is determined using statistical analysis, the area is binarized, and isolated points are removed using a morphological filter operator. The method was tested with ENVISAT Synthetic Aperture Radar and GF-3 SAR data, and results showed that the method was eff ective, and the overall accuracy of the decision reaches 71%. We present two innovations;one is a method that draws a Doppler shift curve, and uses the SAR imaging parameters to determine the detection area of the long wake to achieve rapid detection and reduce the image detection area. The other is where a classical linear fitting method is used to quickly and accurately determine whether the detected dark area is a long ship wake and realizes the twisted long ship wake detection caused by the sea surface flow field, which is otherwise diffi cult to detect by the traditional Radon and Hough transform methods. This method has good suppression performance for the dark spot false alarm formed by low speed wind region or upward flow. The method is developed for maritime ship monitoring system and will promote the operational application of maritime ship monitoring system.展开更多
【目的】基于PI3K/Akt通路研究含凝血酶敏感素基序的去解联金属蛋白酶1(a disintegrin and metalloproteinase with thrombospondin motifs 1,ADAMTS1)在产双胎和单胎蒙古羊发情周期不同阶段卵巢内的表达规律,探究ADAMTS1基因影响蒙古...【目的】基于PI3K/Akt通路研究含凝血酶敏感素基序的去解联金属蛋白酶1(a disintegrin and metalloproteinase with thrombospondin motifs 1,ADAMTS1)在产双胎和单胎蒙古羊发情周期不同阶段卵巢内的表达规律,探究ADAMTS1基因影响蒙古羊繁殖性状的作用机制。【方法】选取经产2次的双胎和单胎蒙古羊共40只,自然发情,确定母羊发情期和间情期,分为双胎发情期、双胎间情期、单胎发情期和单胎间情期组,每组各10只羊。利用注射器抽取2~3岁蒙古羊颗粒细胞,分为对照组和试验组,对照组不添加药物,试验组添加15μmol/L LY294002处理颗粒细胞,分别在24、48和72 h测定细胞活力。通过实时荧光定量PCR技术检测母羊卵巢组织和颗粒细胞内ADAMTS1、PI3K、PTEN、Akt、RPS6、Bcl-2和BAX基因的相对表达量;通过Western blotting技术检测卵巢和颗粒细胞内ADAMTS1、PI3K和Akt蛋白的表达丰度。【结果】实时荧光定量PCR结果显示,双胎发情期组ADAMTS1、Bcl-2基因表达量均显著高于其余各组(P<0.05);双胎发情期组和双胎间情期组PI3K、Akt和PTEN基因表达量均显著高于单胎发情期组和单胎间情期组(P<0.05);单胎间情期组RPS6基因表达量显著低于其余各组(P<0.05);间情期与发情期相比,BAX基因表达显著上调(P<0.05)。Western blotting结果显示,双胎发情期ADAMST1蛋白表达量显著高于其余各组(P<0.05);双胎组与单胎组相比,PI3K和Akt蛋白均表达上调,其中,双胎发情期和双胎间情期PI3K蛋白表达量均显著高于单胎发情期组和单胎间情期组(P<0.05),双胎间情期Akt蛋白表达量最高,显著高于其余各组(P<0.05)。与对照组相比,试验组蒙古羊颗粒细胞形态异常,细胞增殖缓慢,且ADAMTS1、PI3K和Akt基因和蛋白的相对表达量均显著降低(P<0.05)。【结论】ADAMTS1、PI3K和Akt基因和蛋白在蒙古羊卵巢和颗粒细胞内的表达趋势一致,呈正向相关关系,证明ADAMTS1基因PI3K/Akt轴在蒙古羊产双胎性状中发挥重要作用。展开更多
[目的]研究牛活体采卵-体外受精(ovum pick-up and in vitro fertilization,OPU/IVF)体系,建立高效的牛体外胚胎生产系统。[方法]以从屠宰场采集的健康牛新鲜卵巢为试验材料,进行卵母细胞体外成熟、体外受精、体外胚胎培养相关条件的摸...[目的]研究牛活体采卵-体外受精(ovum pick-up and in vitro fertilization,OPU/IVF)体系,建立高效的牛体外胚胎生产系统。[方法]以从屠宰场采集的健康牛新鲜卵巢为试验材料,进行卵母细胞体外成熟、体外受精、体外胚胎培养相关条件的摸索,重点考查体外胚胎培养液中添加瘦素(leptin)对囊胚率的影响。选取13~15月龄健康荷斯坦奶牛及和牛各10头作为供体,进行活体采卵、卵母细胞体外成熟、体外胚胎生产,记录可用卵数及可用囊胚数,统计卵裂率、囊胚率;2个品种牛的体外冷冻胚胎解冻后,以荷斯坦奶牛为受体进行胚胎移植,移植后45 d统计妊娠率。[结果]添加30 U/mL的leptin可以显著(P<0.05)提高屠宰场来源牛体外胚胎的囊胚率。随机选择供体牛活体采卵,平均每头荷斯坦奶牛获得可用卵7.5枚,平均每头和牛获得可用卵8.1枚;荷斯坦奶牛及和牛的卵裂率分别为84.00%、82.71%,二者差异不显著(P>0.05)。体外培养条件下,平均每头荷斯坦奶牛获得可用囊胚4.3枚,平均每头和牛获得可用囊胚3.7枚;荷斯坦奶牛的囊胚率(57.33%)显著(P<0.05)高于和牛(45.68%)。体外胚胎解冻后移植,荷斯坦奶牛胚胎组的妊娠率为54.17%,和牛胚胎组的妊娠率为55.79%,二者差异不显著(P>0.05)。[结论]该研究建立的OPU/IVF体系可以有效提高优质母牛的利用效率,降低生产成本,为牛体外胚胎生产系统的优化提供了参考。展开更多
基金Supported by the National Natural Science Foundation of China(No.41476088)the National High Resolution Project of China(No.41Y30B12-9001-14/16)+1 种基金the 2016 Key Projects for Marine Environmental Security(No.2016YFC14032)the research grants of the Second Institute of Oceanography,MNR(No.JT1307)
文摘The maritime administrative department employs synthetic aperture radar (SAR) satellite remote sensing technology to obtain evidence of illegal discharge of ships. If the ship is discharged during navigation, it forms a long dark wake on the SAR image due to the suppression of the Bragg wave by the oil fi lm. This study investigates key techniques for rapid detection of long ship wakes, thereby providing law enforcement agencies with candidate ships for possible discharge. This paper presents a rapid long ship wake detection method that uses satellite imaging parameters and the axial direction of the ship in images to determine the potential detection area of the wake. Then, the threshold of long ship wake detection is determined using statistical analysis, the area is binarized, and isolated points are removed using a morphological filter operator. The method was tested with ENVISAT Synthetic Aperture Radar and GF-3 SAR data, and results showed that the method was eff ective, and the overall accuracy of the decision reaches 71%. We present two innovations;one is a method that draws a Doppler shift curve, and uses the SAR imaging parameters to determine the detection area of the long wake to achieve rapid detection and reduce the image detection area. The other is where a classical linear fitting method is used to quickly and accurately determine whether the detected dark area is a long ship wake and realizes the twisted long ship wake detection caused by the sea surface flow field, which is otherwise diffi cult to detect by the traditional Radon and Hough transform methods. This method has good suppression performance for the dark spot false alarm formed by low speed wind region or upward flow. The method is developed for maritime ship monitoring system and will promote the operational application of maritime ship monitoring system.
文摘[目的]研究牛活体采卵-体外受精(ovum pick-up and in vitro fertilization,OPU/IVF)体系,建立高效的牛体外胚胎生产系统。[方法]以从屠宰场采集的健康牛新鲜卵巢为试验材料,进行卵母细胞体外成熟、体外受精、体外胚胎培养相关条件的摸索,重点考查体外胚胎培养液中添加瘦素(leptin)对囊胚率的影响。选取13~15月龄健康荷斯坦奶牛及和牛各10头作为供体,进行活体采卵、卵母细胞体外成熟、体外胚胎生产,记录可用卵数及可用囊胚数,统计卵裂率、囊胚率;2个品种牛的体外冷冻胚胎解冻后,以荷斯坦奶牛为受体进行胚胎移植,移植后45 d统计妊娠率。[结果]添加30 U/mL的leptin可以显著(P<0.05)提高屠宰场来源牛体外胚胎的囊胚率。随机选择供体牛活体采卵,平均每头荷斯坦奶牛获得可用卵7.5枚,平均每头和牛获得可用卵8.1枚;荷斯坦奶牛及和牛的卵裂率分别为84.00%、82.71%,二者差异不显著(P>0.05)。体外培养条件下,平均每头荷斯坦奶牛获得可用囊胚4.3枚,平均每头和牛获得可用囊胚3.7枚;荷斯坦奶牛的囊胚率(57.33%)显著(P<0.05)高于和牛(45.68%)。体外胚胎解冻后移植,荷斯坦奶牛胚胎组的妊娠率为54.17%,和牛胚胎组的妊娠率为55.79%,二者差异不显著(P>0.05)。[结论]该研究建立的OPU/IVF体系可以有效提高优质母牛的利用效率,降低生产成本,为牛体外胚胎生产系统的优化提供了参考。
